1. Field of the Invention
The present invention relates to a chemical supply pump, a chemical supply apparatus, and a chemical supply system (a chemical supply method) for accurately supplying a desired quantity of a liquid chemical, in particular, it is suitable for applying to a substrate cleaning apparatus (a substrate cleaning method) for cleaning semiconductor wafers or the like.
2. Description of the Related Art
Conventionally in a semiconductor wet process, used is a substrate cleaning apparatus for performing a process such as cleaning with a cleaning liquid of ultrapure water and a liquid chemical. As such a substrate cleaning apparatus, remarked is a substrate single wafer spin cleaning apparatus in which substrates are loaded one by one and a cleaning liquid is supplied with rotating the substrate in a circumferential direction.
In a conventional substrate cleaning apparatus, it was indispensable to provide a plurality of large-sized cleaning liquid storage tanks for preparing various liquid chemicals at desired concentrations necessary for cleaning. Accordingly, the whole system becomes a very large scale and complex inevitably in this case.
Besides, due to the necessity of providing a plurality of cleaning liquid storage tanks according to the necessary kinds of cleaning liquids as described above, particles are easy to mix in when a cleaning liquid is compounded. Further, generation of particles and (metal) contamination from various liquid-contact portion caused by complication of the substrate cleaning apparatus is in question.
In this manner, at present, it is difficult to avoid increases in scale and complication of the whole apparatus attendant upon an increase in cleaning speed of substrate cleaning apparatus. It is the present state that establishment of a technique of preventing particle-mixing or the like in a cleaning liquid, is eagerly desired.
It is an object of the present invention to provide a chemical supply pump, a chemical supply apparatus, a chemical supply system, a substrate cleaning apparatus, a chemical supply method, and a substrate cleaning method, wherein remarkable miniaturization/simplification of a cleaning liquid supply system including chemical reservoirs (chemical storage tanks) is intended, it becomes possible easily and rapidly to compound and supply a cleaning liquid at an accurate chemical concentration when it is required in cleaning, and it is realized to suppress particles or the like being generated and mixing in a cleaning liquid, to the extremity.
In order to attain the above object, a chemical supply pump of the present invention is a chemical supply pump in which a flow passage for passing a predetermined liquid chemical is formed, a suction valve which is closed by pressure rise of said liquid chemical is provided at a flowing-in port of said flow passage, and a discharge valve which is closed by pressure fall of said liquid chemical is provided at a flowing-out port of said flow passage, wherein at least part of a liquid contact surface in said flow passage is made of a compact member with non-permeability and a high anti-corrosion property to said liquid chemical, and part of said compact member is made into a movable wall, and a shaker connected to said movable wall is provided, and said movable wall is oscillated in a direction substantially perpendicular to its wall surface by drive of said shaker to change the volume of said flow passage periodically.
A chemical supply apparatus of the present invention comprises a chemical supply pump, and a connecting flow passage connecting a supply flow passage that is a passage for a solvent with which said liquid chemical is mixed, and said chemical supply pump, wherein a tubule member directly connecting said supply flow passage is provided in said connecting flow passage. In said chemical supply pump, a flow passage for passing a predetermined liquid chemical is formed, a suction valve which is closed by pressure rise of said liquid chemical is provided at a flowing-in port of said flow passage, and a discharge valve which is closed by pressure fall of said liquid chemical is provided at a flowing-out port of said flow passage, at least part of a liquid contact surface in said flow passage is made of a compact member with non-permeability and a high anti-corrosion property to said liquid chemical, and part of said compact member is made into a movable wall, and a shaker connected to said movable wall is provided, and said movable wall is oscillated in a direction substantially perpendicular to its wall surface by drive of said shaker to change the volume of said flow passage periodically. Said chemical supply apparatus discharges said liquid chemical from said tubule member into said solvent passing through said supply flow passage by drive of said chemical supply pump to compound a mixture solution at a desired concentration.
A chemical supply system of the present invention is a chemical supply system comprising at least one kind of chemical reservoir easy to move, a chemical supply apparatus connected in correspondence to said chemical reservoir, and said supply flow passage. Said chemical supply apparatus comprises a chemical supply pump, and a connecting flow passage connecting the supply flow passage that is a passage for a solvent with which said liquid chemical is mixed, and said chemical supply pump, wherein a tubule member directly connected to said supply flow passage is provided in said connecting flow passage. In said chemical supply pump, a flow passage for passing a predetermined liquid chemical is formed, a suction valve which is closed by pressure rise of said liquid chemical is provided at a flowing-in port of said flow passage, and a discharge valve which is closed by pressure fall of said liquid chemical is provided at a flowing-out port of said flow passage, at least part of a liquid contact surface in said flow passage is made of a compact member with non-permeability and a high anti-corrosion property to said liquid chemical, and part of said compact member is made into a movable wall, and a shaker connected to said movable wall is provided, and said movable wall is oscillated in a direction substantially perpendicular to its wall surface by drive of said shaker to change the volume of said flow passage periodically. Said chemical supply apparatus discharges said liquid chemical from said tubule member into said solvent passing through said supply flow passage by drive of said chemical supply pump to compound a mixture solution at a desired concentration. Said chemical supply system discharges said mixture solution made into the predetermined concentration from a discharge portion provided at an end portion of said supply flow passage, by drive of said chemical supply pump of said chemical supply apparatus.
A substrate cleaning apparatus of the present invention is a substrate cleaning apparatus in which a cleaning liquid is supplied to a set substrate to clean, and comprises a chemical supply system. Said chemical supply system comprises at least one kind of chemical reservoir easy to move, a chemical supply apparatus connected in correspondence to said chemical reservoir, and a supply flow passage. Said chemical supply apparatus discharges said liquid chemical from said tubule member into said solvent passing through said supply flow passage by drive of said chemical supply pump to compound a mixture solution at a desired concentration, and comprises a chemical supply pump, and a connecting flow passage connecting the supply flow passage that is a passage for a solvent with which said liquid chemical is mixed, and said chemical supply pump, wherein a tubule member directly connected to said supply flow passage is provided in said connecting flow passage. In said chemical supply pump, a flow passage for passing a predetermined liquid chemical is formed, a suction valve which is closed by pressure rise of said liquid chemical is provided at a flowing-in port of said flow passage, and a discharge valve which is closed by pressure fall of said liquid chemical is provided at a flowing-out port of said flow passage, at least part of a liquid contact surface In said flow passage is made of a compact member with non-permeability and a high anti-corrosion property to said liquid chemical, and part of said compact member is made into a movable wall, and a shaker connected to said movable wall is provided, and said movable wall is oscillated in a direction substantially perpendicular to its wall surface by drive of said shaker to change the volume of said flow passage periodically. Said substrate cleaning apparatus uses said mixture solution as said cleaning liquid.
A chemical supply method of the present invention is a chemical supply method using a chemical supply pump, wherein, in said chemical supply pump, a flow passage for passing a predetermined liquid chemical is formed, a suction valve which is closed by pressure rise of said liquid chemical is provided at a flowing-in port of said flow passage, and a discharge valve which is closed by pressure fall of said liquid chemical is provided at a flowing-out port of said flow passage, at least part of a liquid contact surface in said flow passage is made of a compact member with non-permeability and a high anti-corrosion property to said liquid chemical, and part of said compact member is made into a movable wall, and a shaker connected to said movable wall is provided, and said movable wall is oscillated in a direction substantially perpendicular to its wall surface by drive of said shaker to change the volume of said flow passage periodically, and said chemical supply pump is driven, and said liquid chemical is discharged into a solvent passing through said supply flow passage to compound a mixture solution at a desired concentration.
A substrate cleaning method of the present invention is a substrate cleaning method in which a cleaning liquid is supplied to a set substrate to clean, wherein a chemical supply pump Is used in which a flow passage for passing a predetermined liquid chemical is formed, a suction valve which is closed by pressure rise of said liquid chemical is provided at a flowing-in port of said flow passage, and a discharge valve which is closed by pressure fall of said liquid chemical is provided at a flowing-out port of said flow passage, at least part of a liquid contact surface in said flow passage is made of a compact member with non-permeability and a high anti-corrosion property to said liquid chemical, and part of said compact member is made into a movable wall, and a shaker connected to said movable wall is provided, and said movable wall is oscillated in a direction substantially perpendicular to its wall surface by drive of said shaker to change the volume of said flow passage periodically, and said chemical supply pump is driven, said liquid chemical is discharged into a solvent passing through said supply flow passage, a mixture solution at a desired concentration is compounded, and said mixture solution is used as said cleaning liquid to clean said substrate surface.
A chemical supply system of the present invention is a chemical supply system for supplying a mixture solution in which a liquid chemical is mixed and diluted with a solvent, comprising at least one kind of chemical reservoir easy to move, in which said liquid chemical at a high concentration is stored, a chemical supply means for sucking a predetermined quantity of said liquid chemical from said chemical reservoir and feeding out it, and a piping system forming a flow passage for said solvent connected to said chemical supply means, and having a discharge portion for said solution at an end portion, wherein, at the time of use, a necessary quantity of said liquid chemical is mixed with said solution flowing in said piping system, said mixture solution at a desired concentration is produced, and said mixture solution is supplied from said discharge portion.
According to a chemical supply pump of the present invention, a movable wall is driven and controlled by a shaker to oscillate, and a liquid chemical is discharged by the pressure, and a desired quantity of the liquid chemical can be discharged and supplied with accuracy. Here, used is a compact member, preferably, amorphous carbon, that at least part of the liquid contact surface has non-permeability and a high anti-corrosion property to the liquid chemical. This amorphous carbon is a material easy to control its porosity, and one whose porosity is substantially zero is very superior in non-permeability and the high anti-corrosion property. Accordingly, by providing this amorphous carbon on the important portion of the liquid contact surface, the supply quantity control of the liquid chemical becomes more accurate, and mixing of particles or the like into the liquid chemical is suppressed.
Further in the present invention, provided is a chemical supply apparatus including this chemical supply pump as a component. This chemical supply apparatus mixes a liquid chemical from a tubule member with a solvent whose representative is ultrapure water passing through a supply flow passage by drive of the chemical supply pump, and mixture solutions at various concentrations can easily be compounded at need. Here, in case that the discharge direction of the liquid chemical is a direction substantially perpendicular to the flow direction of the above solvent, by applying a pressure to the liquid chemical such that the linear velocity of the liquid chemical discharged from the tubule member is sufficiently greater than the linear velocity of the solvent passing through the supply flow passage, the liquid chemical reaches the opposite wall surface of the supply flow passage in the solvent, and a mixture solution at a uniform concentration is compounded in a moment.
Further in the present invention, provided is a chemical supply system including this chemical supply apparatus as a component and for supplying the above mixture solution. In this chemical supply system, because it is possible to produce mixture solutions at desired concentrations at need as described above, enough is the easily movable small-sized reservoir for the liquid chemical that is the formulated concentrate. That is, in this chemical supply system, there is no necessity of providing very large reservoirs for mixture solutions different in chemical concentration and kind as conventionally, and not only particle mixing to a cleaning liquid, or the like, can be suppressed, but also remarkable reduction/simplification of the scale of the whole system can be realized. Accordingly, by applying this chemical supply system to, e.g., a substrate cleaning apparatus, it becomes possible rapidly and easily to supply various pure cleaning liquids (mixture solutions) different in concentration and kind.
Accordingly, according to the present invention, remarkable miniaturization/simplification of a cleaning liquid supply system including chemical reservoirs (chemical storage tanks) is intended, it becomes possible easily and rapidly to compound and supply a cleaning liquid at an accurate chemical concentration when it is required in cleaning, and it is realized to suppress particles or the like being generated and mixing in a cleaning liquid, to the extremity.